19-2877; Rev 0; 5/03 MAX1582 Evaluation Kit Component Suppliers SUPPLIER PHONE WEBSITE Central Semiconductor 631-435-1110 www.centralsemi.com Kamaya 260-489-1533 www.kamaya.com Murata 814-237-1431 www.murata.com Nichia 248-352-6575 www.nichia.com Panasonic 714-373-7939 www.panasonic.com Sumida 847-956-0666 www.sumida.com Taiyo Yuden 408-573-4150 www.t-yuden.com TDK 847-803-6100 www.component.tdk.com TOKO 847-297-0070 www.toko.com Features ♦ Constant Current Regulation for Uniform Illumination ♦ Up to 84% Efficiency ♦ Flexible Analog or PWM Dimming Control ♦ Low 15mVP-P Input Ripple ♦ 0.9W Output Power with Internal 30V MOSFET Switch ♦ Output Overvoltage Protection Eliminates Zener Diode ♦ Small, Low-Profile Components ♦ 2.6V to 5.5V Input Range ♦ 0.01µA Shutdown Current ♦ Thin QFN 4mm x 4mm IC Package ♦ Fully Assembled and Tested Ordering Information PART MAX1582EVKIT TEMP RANGE IC PACKAGE -30°C to +85°C 12 Thin QFN Note: When contacting these suppliers, please specify you are using the MAX1582. Component List DESIGNATION QTY DESCRIPTION C1 C2 C3 1 1 1 2.2µF, 6.3V X5R capacitor (0603) Taiyo Yuden JMK107BJ225KA, or Panasonic ECJ1VB0J225M, or equivalent 0.1µF, 50V X7R capacitor (0603) TDK C1608X7R1H104KT or equivalent 0.022µF X7R capacitor (0603) Taiyo Yuden TMK107BJ223KA or equivalent D1 1 30V, 200mA Schottky diode (SOD323) Central CMDSH2-3 D2–D7 6 White LEDs Nichia NSCW215T DESIGNATION QTY DESCRIPTION JU1, JU2 2 3-pin headers JU3 1 2-pin header L1 1 22µH inductor (1210) 250mA, 710mΩ, 2.5 mm x 2.2 mm x 2.0mm Murata LQH32CN220K R1 1 7.5Ω ±1% resistor (0603) R2 1 100kΩ ±5% resistor (0603) U1 1 MAX1582ETC (12-pin thin QFN 4 x 4) U2 1 MAX1582EBE (UCSP 4 x 4) None 3 Shunts None 1 MAX1582 EV kit PC board ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 Evaluates: MAX1582 General Description The MAX1582 evaluation kit (EV kit) is a fully assembled and tested circuit board that evaluates the MAX1582 white LED step-up converter. The circuit operates from 2.6V to 5.5V and delivers 0 to 20mA to light a series of up to six white LEDs. The evaluation kit has two groups of white LEDs—a main group with four LEDs, and a subgroup with two LEDs. These two groups of LEDs have independent shutdown/enable control through jumpers provided on the board. A flexible dimming feature allows the LED brightness to be controlled with either an analog voltage or a PWM signal. Evaluates: MAX1582 MAX1582 Evaluation Kit Quick Start Follow the steps below to verify board operation. Do not turn on the power supply until all connections are completed: 1) Verify the shunts on JU1 and JU2 are across pins 2 and 3. 2) 3) 4) 5) Verify that a shunt is across the pins of jumper JU3. Preset the power supply to between 2.6V and 5.5V. Turn off the power supply. Connect the power-supply positive terminal to the V+ pad on the EV kit. 6) Connect the power-supply ground terminal to the GND pad on the EV kit. 7) Turn on the power supply and verify that the LEDs are lit. Detailed Description Enable/Shutdown The LEDs on the MAX1582 EV kit are divided into two groups—a main group consisting of D2–D5 and a subgroup consisting of D6 and D7. Connect pins 2 and 3 of JU1 to enable the main LED group, or connect pins 1 and 2 to disable the main LED group. Connect pins 2 and 3 of JU2 to enable the subgroup, or connect pins 1 and 2 to disable the subgroup (Table 1). If both LED groups are disabled, then the IC enters low-power shutdown mode. Controlling LED Intensity LED intensity is controlled using the CTRL input. CTRL is used either as an analog input or a digital PWM input. When using CTRL as an analog input, connect a 0 to 1.62V voltage source to CTRL, where 0V corresponds to the dimmest setting, and 1.62V is full brightness. Exceeding 1.62V does not increase brightness. For digital dimming, connect a PWM signal (200Hz to 200kHz) directly to CTRL. In this case, the duty cycle controls the brightness of the LEDs, where 0% duty cycle corresponds to zero current and 100% duty cycle corresponds to full current. PWM signal VIL should equal 0V and VIH should exceed 1.62V. A pullup resistor and jumper (R2 and JU3) are provided so the evaluation kit can be used without an external connection to CTRL. With JU3 shorted and no other connection to CTRL, the LEDs are set to full brightness. If CTRL is being driven, the shunt across JU3 can be removed. Remove the shunt across JU3 when measuring quiescent current with the circuit in shutdown mode; otherwise excessive current is measured. Table 1. Jumper Functions JUMPER JU1 JU2 JU3 JU4 JU5 JU6 2 POSITION FUNCTION LEDs AFFECTED D2–D5 (main group) 1, 2 Disable 2, 3 Enable 1, 2 Disable 2, 3 Enable D6, D7 (subgroup) Short 100kΩ pullup resistor connected from CTRL to V+. Open CTRL open—must be driven externally. Short Shorts D2 so only D3, D4, and D5 are used in the LED main group. Open All four LEDs (D2–D5) are used. Short LED main group connected. Open LED main group disconnected; connect external LEDs from OUT1 to OUT2. Short LED subgroup connected. Open LED subgroup disconnected; connect external LEDs from OUT2 to CS. _______________________________________________________________________________________ MAX1582 Evaluation Kit Evaluates: MAX1582 V+ V+ OUT1 C1 2.2µF L1 22µH JU3 1 V+ 2 R2 100kΩ CTRL 3 6 V+ V+ EN1 3 2 1 JU1 3 2 1 7 4 JU2 C3 0.022µF LX U1 VP CTRL MAX1582ETC OUT1 PGND EN1 OUT2 EN2 CS COMP JU5 SHORT D1 11 D2 10 C2 0.1µF 12 GND EP JU4 OPEN 2 D3 9 8 3 JU6 SHORT 12 D4 5 1 16 4 D6 V+ VP U2 LX 9 MAX1582EBE OUT1 13 CTRL PGND EN1 OUT2 EN2 CS COMP GND 5 14 15 8 D5 EN2 D7 GND OUT2 CS R1 7.5Ω Figure 1. MAX1582 EV Kit Schematic Changing the Number of LEDs Connecting External LEDs The MAX1582 can be used to drive a total of up to six LEDs, and the MAX1582 EV kit comes configured for driving six LEDs. To evaluate the MAX1582 driving fewer than six LEDs, short out the pads of the unused LEDs. To prevent excessive leakage in shutdown, there must be at least two white LEDs in the circuit. For accurate dimming control, there must be at least two white LEDs in each group. If dimming is not required, this can be reduced to one LED per group. For convenience, JU4 can be used to short D2, reducing the number of main LEDs to three. Although the MAX1582 EV kit comes with surfacemount LEDs installed, it can also be used to drive external LEDs. For the main group, cut the PC board trace shorting JU5, and connect a series string of two to six white LEDs from OUT1 to OUT2. Connect the anode to OUT1 and the cathode to OUT2. For the subgroup, cut the PC board trace shorting JU6 and connect a series string of two to three white LEDs from OUT2 to CS. Connect the anode to OUT2 and the cathode to CS. Ensure the total number of subgroup LEDs does not exceed three. _______________________________________________________________________________________ 3 Evaluates: MAX1582 MAX1582 Evaluation Kit Figure 2. MAX1582 EV Kit Component Placement Guide— Component Side Figure 3. MAX1582 EV Kit PC Board Layout—Component Side Figure 4. MAX1582 EV Kit PC Board Layout—Solder Side Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 4 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2003 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.